// Ex9_08.cpp
  // Using a base class pointer to call a virtual function
  include <iostream>
  include <GlassBox.h>                  // For CBox and CGlassBox
  using std::cout;
  using std::endl;
  
  int main()
  {
    CBox myBox(2.0, 3.0, 4.0);            // Declare a base box
    CGlassBox myGlassBox(2.0, 3.0, 4.0);  // Declare derived box of same size
    CBox* pBox = 0;            // Declare a pointer to base class objects
  
    pBox = &myBox;             // Set pointer to address of base object
    pBox->ShowVolume();        // Display volume of base box
    pBox = &myGlassBox;        // Set pointer to derived class object
    pBox->ShowVolume();        // Display volume of derived box
  
    cout << endl;
    return 0;
  }